1. Field of the Invention
The present invention relates to a private automatic branch exchange (PABX) having an internet gateway, and more particularly, to an apparatus and method for recording and reproducing an outgoing voice message.
2. Description of the Related Art
A typical PABX system is connected to a public switched telephone network (PSTN) for affecting the central office line communication loop and the internal communication loop. As the internet becomes popular, the PABX has evolved in a direction to provide voice and data service to subscribers of the internet as well as the PSTN. The “Internet Gateway” connects the PABX to the internet and allows the PABX to provide internet service to subscribers. Such PABXs are configured as shown in FIG. 1. In this diagram, the PABXs A and B are connected to the internet via a built-in or a separately procured gateway and coupled to the PSTN for providing voice and data services to subscribers A and B.
The PABX has been developed to offer subscribers with more services. A major illustrative example is a voice message feature used to make an announcement or automatic answering service to subscribers. This service is achieved by a voice mailing system (VMS) that is linked to the exchange system.
In order to provide the voice message as an announcement or automatic answering message, the conventional PABX requires a VMS, which is connected to the exchange system, and the voice message must be pre-recorded in the VMS. Such implementation is not economical or convenient. Further, the VMS recording is performed based on the PCM (Pulse Code Modulation) technique according to the ITU-T Recommendation G.711, thus producing an undesirably large amount of data. As a result, the memory is not used efficiently.